"Regulators in the US are being urged to investigate any potential online advertising and search partnership between Google and Yahoo. It has been widely reported that it is looking into the anti-trust implications of last month's two-week test. However, the department says it has no comment on the coalition's demands because there is no definitive agreement between Yahoo and Google at the moment.
But reports say that the two companies are presently hammering out the intricacies of a future potential advertising and search agreement, and are sharing their plans with antitrust regulators."